Postby smj999smj » Thu May 09, 2024 11:12 am
IMO, the Hitachi coils from Rockauto.com are the best bang for the buck at around $34 each. Hitachi does make a lot of original equipment parts for Nissan, from alternators to ignition components to even water pumps. Hitachi coils may be an upgrade over what comes in the VQ40DE from the factory, which is Hanshin. Hanshin is a name I remember well from back in my Nissan tech days as they made the coil packs in the 92-94 Maxima SE with the 190-HP, VE30DE DOHC-V6. Back in the day, we would get customers coming into the shop with these cars saying they were driving and heard a loud "bang" and found their muffler had exploded! It was found that these Hanshin ignition coil packs would fail, and unburned fuel would get into the exhaust system to the point that it would ignite and blow-up the muffler! Now, if somebody told me that, I'd think, "BS!" However, I was there at the Nissan dealer when these cars were brought in and saw the damage for myself. It was often hard to identify the coil pack that was failing as they would operate fine when cold but would fail when hot. They were large coils compared to what we have in our Nissan engines, today. Sometimes, you could see cracks on the body of the coil that were a sign of it failing. Many time, Nissan tech support would have as replace a bank of coil packs and cross our fingers. If that didn't work, we'd replaced the other bank. I'm not saying all Hanshin ignition coils are bad or worse than Hitachi or any other brands; they do well in the VQ engines, and no coil pack is meant to last forever. I just still have those memories of blown-up Maxima SE mufflers!
I seriously considered going the Audi R8 coil pack route when I replace the valve covers and plugs on my N50 Xterra. Reading about the hard start issues made me leery. The Z1 coil packs looked great but are expensive! Then they put them on sale with a big discount and I decided to pick up a set of them which I'll run with a set of NGK Ruthenium HX spark plugs (best bang for the buck plugs for the VQ40DE, IMO). Whether I notice a difference in performance has yet to be seen.
With my 2006 R51 (before the tree landed on it and killed it), the only noticeable increases in performance came from installing the XTP plenum spacer and the Superchips Flashpaq tuner. While I used the 91-octane tune with bumping the ignition timing 3-degrees, it even made a noticeable bump in performance in the 87-octane performance mode. Unfortunately, the software update got rid of the WOT eliminator feature it had and it is only good up through 2010 models. Superchips also stopped selling and supporting that model tuner. The rest of the upgrades, as I've mentioned in years past, were a waste of money and time, IMO. The DT shorty headers and mid-pipes, the aFe Momentum GT CAI, and the Magnaflow 12580 muffler that eliminated the so-called "restrictive Y" in the exhaust, along with the Superchips 91 tune and plenum spacer, only saw me a gain of 1-second in the 06 Pathfinder LE's 0-60 time and 1/4-mile time. So, that's significant if one drag races their R51, but most of us don't, and therefore from a practical sense, it doesn't make much sense to spend that much money and time for what's primarily a daily driver and light off-road use vehicle. It also came with a light of exhaust "drone" during light and medium acceleration, although sounded good at WOT.
